Leg ulcers are a common and complex clinical challenge that affect the lower limbs—most often below the knee and on the feet. These wounds, which arise due to poor blood flow, pressure, or injury, can cause chronic discomfort, infection, and reduced mobility.
Whether you're a medical student, healthcare professional, or patient trying to understand chronic wounds better, this comprehensive guide will help you recognize the different causes of leg ulceration, interpret their appearance, and identify appropriate treatments.
What is Leg Ulceration?
A leg ulcer is defined as an open sore on the lower limb due to a break in the skin that fails to heal spontaneously. It’s usually caused by underlying venous, arterial, neuropathic, or systemic conditions. Ulcers below the knee, especially on the medial ankle or foot, are the most commonly seen.
Ulcers can be painless or painful, acute or chronic, and can arise from vascular, neuropathic, or neoplastic causes.
Key Diagnostic Approach: Pain and History
The first step in evaluation is determining if the ulcer is:
- Painful: Often ischemic or infected
- Painless: May suggest neuropathic or venous origin
Then, evaluate the history:
- Diabetic status
- Past trauma or vascular surgery
- Signs of venous insufficiency or arterial compromise
Causes of Leg Ulceration
1. Venous Ulcers
Venous leg ulcers are the most common type, accounting for over 70% of chronic leg wounds.
Cause: Venous hypertension due to varicose veins or previous DVT
Location: Medial ankle, above the malleolus
Appearance:
- Shallow, irregular margins
- Weeping and exudative
- Associated lipodermatosclerosis
- Bleeds easily
Diagnosis:
- Duplex ultrasound to assess venous insufficiency
Treatment:
- 4-layer compression bandaging
- Treat underlying varicosities
- Elevation and exercise
2. Arterial (Ischemic) Ulcers
Cause: Peripheral arterial disease
Location: Lateral ankle, heel, toes, metatarsal heads
Appearance:
- Painful, punched-out edges
- Dry, necrotic base
- Blue toes or pallor may be present
Diagnosis:
- ABI (Ankle-Brachial Index)
- Duplex or angiography
Treatment:
- Treat ischemia: Medical therapy, angioplasty ± stent, bypass surgery
- Avoid compression therapy
3. Diabetic Foot Ulcers
Diabetic patients may present with:
- Neuropathic ulcers (painless, pressure points)
- Ischemic ulcers (painful, distal sites)
Location: Plantar foot, heels, metatarsals, toes
Appearance:
- Deep, surrounded by callus
- Risk of cellulitis, abscess, and osteomyelitis
Treatment:
- Improve glycemic control
- Podiatric care, debridement
- Offloading (special footwear)
- Treat infection
4. Malignant Ulcers
May arise as:
- Squamous Cell Carcinoma (Marjolin’s ulcer): Chronic non-healing ulcers
- Basal Cell Carcinoma: Pearly edges, rolled margins
- Melanoma: Pigmented or bleeding ulcers
Diagnosis:
- Biopsy: Always indicated for chronic ulcers worsening despite treatment
Treatment:
- Surgical excision and oncologic management
5. Pressure Ulcers (Neuropathic Ulcers)
Often found in bedridden or paraplegic patients with pressure over bony prominences or in diabetics with peripheral neuropathy.
Location: Heel, sacrum, metatarsal heads, toes
Appearance:
- Deep, painless, with callus
- Commonly infected
Treatment:
- Pressure relief and offloading
- Infection control
- Surgical debridement if needed
6. Miscellaneous Ulcers
- Traumatic: Lacerations in poor circulation
- Infectious: TB, syphilis, tropical ulcers
- Autoimmune/Vasculitis: SLE, RA-related
- Pyoderma Gangrenosum: Necrotic, violaceous ulcers in IBD
Sites of Leg Ulcers by Etiology
| Etiology | Common Sites |
|---|---|
| Venous | Medial calf, medial ankle |
| Arterial | Lateral malleolus, toes, heels |
| Neuropathic | Heel, metatarsals, plantar toes |
| Vasculitis | Anterior shin |
Red Flags for Malignancy in Ulcers
- Rapid change in size
- Bleeding or itching
- Rolled, everted edges
- Heaped up base
- Lymphadenopathy
Always perform a biopsy if:
- Chronic ulcer >3 months
- Fails to heal despite appropriate care
- Suspicious margins or pigmentation
Key Investigations in Leg Ulceration
| Test | Purpose |
|---|---|
| FBC | Check for infection/inflammation |
| Glucose | Rule out diabetes |
| TPHA, ANCA, ANA, RF | Identify autoimmune or infectious causes |
| ABI & Toe Pressure | Rule out Peripheral Arterial Disease |
| Duplex Ultrasound | Assess venous competence |
| Biopsy | Rule out malignancy |
Treatment Overview by Cause
| Ulcer Type | First-Line Treatment |
|---|---|
| Venous | Compression therapy (4-layer bandaging) |
| Arterial | Angioplasty / Bypass surgery |
| Neuropathic | Offloading, glycemic control |
| Malignant | Surgical excision |
| Infectious | Antibiotics and wound care |
| Autoimmune | Immunosuppressants |
| Mixed ulcers | Multidisciplinary approach |
Healing Principles in Chronic Ulcers
- Address underlying cause (vascular, diabetic, pressure, etc.)
- Optimize nutrition and glycemic control
- Regular debridement of necrotic tissue
- Avoid inappropriate topical agents
- Use advanced dressings only when indicated (hydrogels, foams)
Prevention Strategies
- Compression stockings for venous insufficiency
- Foot care education for diabetics
- Early revascularization for PAD
- Regular follow-up for chronic ulcer patients
- Avoiding trauma and pressure points
FAQs on Leg Ulcers
Q1. What is the most common cause of leg ulcers?
Venous insufficiency is the most common cause, especially in elderly or immobile patients.
Q2. How long does a leg ulcer take to heal?
Venous ulcers can take weeks to months; healing depends on treating the underlying cause.
Q3. When should I see a doctor for a leg ulcer?
If the ulcer is painful, spreading, foul-smelling, or not healing within 2 weeks—medical attention is necessary.
Q4. Can leg ulcers be prevented?
Yes. Managing diabetes, maintaining vascular health, wearing compression stockings, and avoiding injuries are essential preventive strategies.
Q5. Is surgery required for leg ulcers?
Only in specific cases like arterial ulcers requiring bypass, or malignant ulcers needing excision.
Final Thoughts
Leg ulceration is not a disease but a symptom of an underlying pathology. Identifying whether it is venous, arterial, neuropathic, malignant, or traumatic is the cornerstone of effective management. Without addressing the root cause, no amount of local treatment will lead to permanent healing.
Through a structured approach—pain assessment, site evaluation, investigations, and cause-based treatment—long-term healing and quality of life can be achieved for those suffering from chronic leg wounds.
